| Message ID | 20181029174059.38326-3-olga.kornievskaia@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v5,01/12] VFS: move cross device copy_file_range() check into filesystems | expand |
On Mon, Oct 29, 2018 at 7:41 PM Olga Kornievskaia <olga.kornievskaia@gmail.com> wrote: > > From: Olga Kornievskaia <kolga@netapp.com> > > This patch makes it the responsibility of individual filesystems to > allow or deny cross device copies. Both NFS and CIFS have operations > for cross-server copies, and later patches will implement this feature. > > Note that as of this patch, the copy_file_range() function might be passed > superblocks from different filesystem types. -EXDEV should be returned > if cross device copies aren't supported. This Note is not ok. As Dave commented, you shoud make this change in a separate path. I will explain... > > Reviewed-by: Amir Goldstein <amir73il@gmail.com> > Reviewed-by: Matthew Wilcox <willy@infradead.org> > Reviewed-by: Steve French <stfrench@microsoft.com> > Reviewed-by: Jeff Layton <jlayton@kernel.org> > Signed-off-by: Olga Kornievskaia <kolga@netapp.com> > --- > Documentation/filesystems/porting | 7 +++++++ > fs/cifs/cifsfs.c | 3 +++ > fs/nfs/nfs4file.c | 3 +++ > fs/overlayfs/file.c | 3 +++ > fs/read_write.c | 7 ++----- > 5 files changed, 18 insertions(+), 5 deletions(-) > > diff --git a/Documentation/filesystems/porting b/Documentation/filesystems/porting > index 7b7b845..897e1e7 100644 > --- a/Documentation/filesystems/porting > +++ b/Documentation/filesystems/porting > @@ -622,3 +622,10 @@ in your dentry operations instead. > alloc_file_clone(file, flags, ops) does not affect any caller's references. > On success you get a new struct file sharing the mount/dentry with the > original, on failure - ERR_PTR(). > +-- > +[mandatory] > + ->copy_file_range() may now be passed files which belong to two > + different superblocks of the same file system type or which belong > + to two different filesystems types all together. As before, the > + destination's copy_file_range() is the function which is called. > + If it cannot copy ranges from the source, it should return -EXDEV. > diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c > index 7065426..ca8fc87 100644 > --- a/fs/cifs/cifsfs.c > +++ b/fs/cifs/cifsfs.c > @@ -1114,6 +1114,9 @@ static ssize_t cifs_copy_file_range(struct file *src_file, loff_t off, > unsigned int xid = get_xid(); > ssize_t rc; > > + if (file_inode(src_file)->i_sb != file_inode(dst_file)->i_sb) > + return -EXDEV; > + > rc = cifs_file_copychunk_range(xid, src_file, off, dst_file, destoff, > len, flags); > free_xid(xid); > diff --git a/fs/nfs/nfs4file.c b/fs/nfs/nfs4file.c > index 4288a6e..5a73c90 100644 > --- a/fs/nfs/nfs4file.c > +++ b/fs/nfs/nfs4file.c > @@ -135,6 +135,9 @@ static ssize_t nfs4_copy_file_range(struct file *file_in, loff_t pos_in, > { > ssize_t ret; > > + if (file_inode(file_in)->i_sb != file_inode(file_out)->i_sb) > + return -EXDEV; > + > if (file_inode(file_in) == file_inode(file_out)) > return -EINVAL; > retry: > diff --git a/fs/overlayfs/file.c b/fs/overlayfs/file.c > index aeaefd2..0331e33 100644 > --- a/fs/overlayfs/file.c > +++ b/fs/overlayfs/file.c > @@ -483,6 +483,9 @@ static ssize_t ovl_copy_file_range(struct file *file_in, loff_t pos_in, > struct file *file_out, loff_t pos_out, > size_t len, unsigned int flags) > { > + if (file_inode(file_in)->i_sb != file_inode(file_out)->i_sb) > + return -EXDEV; > + > return ovl_copyfile(file_in, pos_in, file_out, pos_out, len, flags, > OVL_COPY); > } > diff --git a/fs/read_write.c b/fs/read_write.c > index 39b4a21..7a912e3 100644 > --- a/fs/read_write.c > +++ b/fs/read_write.c > @@ -1575,10 +1575,6 @@ ssize_t vfs_copy_file_range(struct file *file_in, loff_t pos_in, > (file_out->f_flags & O_APPEND)) > return -EBADF; > > - /* this could be relaxed once a method supports cross-fs copies */ > - if (inode_in->i_sb != inode_out->i_sb) > - return -EXDEV; > - IMO, series will look the least awkward, if you start with "moving" this check to before file_in->f_op->clone_file_range() AND before file_in->f_op->copy_file_range(). The title of the patch would be something like: "VFS: generic cross-device copy_file_range() support for all filesystems" (Dave's suggested commit message) Then, in the next patch, which is this patch you posted "VFS: move cross device copy_file_range() check into filesystems" You will only need to remove the same fs check from before file_in->f_op->copy_file_range() and add it inside filesystems. I hope that is clear. Thanks, Amir.
On Mon, Oct 29, 2018 at 2:03 PM Amir Goldstein <amir73il@gmail.com> wrote: > > On Mon, Oct 29, 2018 at 7:41 PM Olga Kornievskaia > <olga.kornievskaia@gmail.com> wrote: > > > > From: Olga Kornievskaia <kolga@netapp.com> > > > > This patch makes it the responsibility of individual filesystems to > > allow or deny cross device copies. Both NFS and CIFS have operations > > for cross-server copies, and later patches will implement this feature. > > > > Note that as of this patch, the copy_file_range() function might be passed > > superblocks from different filesystem types. -EXDEV should be returned > > if cross device copies aren't supported. > > This Note is not ok. > As Dave commented, you shoud make this change in a separate path. > I will explain... > > > > > Reviewed-by: Amir Goldstein <amir73il@gmail.com> > > Reviewed-by: Matthew Wilcox <willy@infradead.org> > > Reviewed-by: Steve French <stfrench@microsoft.com> > > Reviewed-by: Jeff Layton <jlayton@kernel.org> > > Signed-off-by: Olga Kornievskaia <kolga@netapp.com> > > --- > > Documentation/filesystems/porting | 7 +++++++ > > fs/cifs/cifsfs.c | 3 +++ > > fs/nfs/nfs4file.c | 3 +++ > > fs/overlayfs/file.c | 3 +++ > > fs/read_write.c | 7 ++----- > > 5 files changed, 18 insertions(+), 5 deletions(-) > > > > diff --git a/Documentation/filesystems/porting b/Documentation/filesystems/porting > > index 7b7b845..897e1e7 100644 > > --- a/Documentation/filesystems/porting > > +++ b/Documentation/filesystems/porting > > @@ -622,3 +622,10 @@ in your dentry operations instead. > > alloc_file_clone(file, flags, ops) does not affect any caller's references. > > On success you get a new struct file sharing the mount/dentry with the > > original, on failure - ERR_PTR(). > > +-- > > +[mandatory] > > + ->copy_file_range() may now be passed files which belong to two > > + different superblocks of the same file system type or which belong > > + to two different filesystems types all together. As before, the > > + destination's copy_file_range() is the function which is called. > > + If it cannot copy ranges from the source, it should return -EXDEV. > > diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c > > index 7065426..ca8fc87 100644 > > --- a/fs/cifs/cifsfs.c > > +++ b/fs/cifs/cifsfs.c > > @@ -1114,6 +1114,9 @@ static ssize_t cifs_copy_file_range(struct file *src_file, loff_t off, > > unsigned int xid = get_xid(); > > ssize_t rc; > > > > + if (file_inode(src_file)->i_sb != file_inode(dst_file)->i_sb) > > + return -EXDEV; > > + > > rc = cifs_file_copychunk_range(xid, src_file, off, dst_file, destoff, > > len, flags); > > free_xid(xid); > > diff --git a/fs/nfs/nfs4file.c b/fs/nfs/nfs4file.c > > index 4288a6e..5a73c90 100644 > > --- a/fs/nfs/nfs4file.c > > +++ b/fs/nfs/nfs4file.c > > @@ -135,6 +135,9 @@ static ssize_t nfs4_copy_file_range(struct file *file_in, loff_t pos_in, > > { > > ssize_t ret; > > > > + if (file_inode(file_in)->i_sb != file_inode(file_out)->i_sb) > > + return -EXDEV; > > + > > if (file_inode(file_in) == file_inode(file_out)) > > return -EINVAL; > > retry: > > diff --git a/fs/overlayfs/file.c b/fs/overlayfs/file.c > > index aeaefd2..0331e33 100644 > > --- a/fs/overlayfs/file.c > > +++ b/fs/overlayfs/file.c > > @@ -483,6 +483,9 @@ static ssize_t ovl_copy_file_range(struct file *file_in, loff_t pos_in, > > struct file *file_out, loff_t pos_out, > > size_t len, unsigned int flags) > > { > > + if (file_inode(file_in)->i_sb != file_inode(file_out)->i_sb) > > + return -EXDEV; > > + > > return ovl_copyfile(file_in, pos_in, file_out, pos_out, len, flags, > > OVL_COPY); > > } > > diff --git a/fs/read_write.c b/fs/read_write.c > > index 39b4a21..7a912e3 100644 > > --- a/fs/read_write.c > > +++ b/fs/read_write.c > > @@ -1575,10 +1575,6 @@ ssize_t vfs_copy_file_range(struct file *file_in, loff_t pos_in, > > (file_out->f_flags & O_APPEND)) > > return -EBADF; > > > > - /* this could be relaxed once a method supports cross-fs copies */ > > - if (inode_in->i_sb != inode_out->i_sb) > > - return -EXDEV; > > - > > IMO, series will look the least awkward, if you start with "moving" > this check to before > file_in->f_op->clone_file_range() AND before file_in->f_op->copy_file_range(). > The title of the patch would be something like: > "VFS: generic cross-device copy_file_range() support for all filesystems" > (Dave's suggested commit message) > > Then, in the next patch, which is this patch you posted > "VFS: move cross device copy_file_range() check into filesystems" > > You will only need to remove the same fs check from before > file_in->f_op->copy_file_range() and add it inside filesystems. > > I hope that is clear. > You want to make the side-effect into the first class citizen. Ok.
diff --git a/Documentation/filesystems/porting b/Documentation/filesystems/porting index 7b7b845..897e1e7 100644 --- a/Documentation/filesystems/porting +++ b/Documentation/filesystems/porting @@ -622,3 +622,10 @@ in your dentry operations instead. alloc_file_clone(file, flags, ops) does not affect any caller's references. On success you get a new struct file sharing the mount/dentry with the original, on failure - ERR_PTR(). +-- +[mandatory] + ->copy_file_range() may now be passed files which belong to two + different superblocks of the same file system type or which belong + to two different filesystems types all together. As before, the + destination's copy_file_range() is the function which is called. + If it cannot copy ranges from the source, it should return -EXDEV. diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c index 7065426..ca8fc87 100644 --- a/fs/cifs/cifsfs.c +++ b/fs/cifs/cifsfs.c @@ -1114,6 +1114,9 @@ static ssize_t cifs_copy_file_range(struct file *src_file, loff_t off, unsigned int xid = get_xid(); ssize_t rc; + if (file_inode(src_file)->i_sb != file_inode(dst_file)->i_sb) + return -EXDEV; + rc = cifs_file_copychunk_range(xid, src_file, off, dst_file, destoff, len, flags); free_xid(xid); diff --git a/fs/nfs/nfs4file.c b/fs/nfs/nfs4file.c index 4288a6e..5a73c90 100644 --- a/fs/nfs/nfs4file.c +++ b/fs/nfs/nfs4file.c @@ -135,6 +135,9 @@ static ssize_t nfs4_copy_file_range(struct file *file_in, loff_t pos_in, { ssize_t ret; + if (file_inode(file_in)->i_sb != file_inode(file_out)->i_sb) + return -EXDEV; + if (file_inode(file_in) == file_inode(file_out)) return -EINVAL; retry: diff --git a/fs/overlayfs/file.c b/fs/overlayfs/file.c index aeaefd2..0331e33 100644 --- a/fs/overlayfs/file.c +++ b/fs/overlayfs/file.c @@ -483,6 +483,9 @@ static ssize_t ovl_copy_file_range(struct file *file_in, loff_t pos_in, struct file *file_out, loff_t pos_out, size_t len, unsigned int flags) { + if (file_inode(file_in)->i_sb != file_inode(file_out)->i_sb) + return -EXDEV; + return ovl_copyfile(file_in, pos_in, file_out, pos_out, len, flags, OVL_COPY); } diff --git a/fs/read_write.c b/fs/read_write.c index 39b4a21..7a912e3 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -1575,10 +1575,6 @@ ssize_t vfs_copy_file_range(struct file *file_in, loff_t pos_in, (file_out->f_flags & O_APPEND)) return -EBADF; - /* this could be relaxed once a method supports cross-fs copies */ - if (inode_in->i_sb != inode_out->i_sb) - return -EXDEV; - if (len == 0) return 0; @@ -1588,7 +1584,8 @@ ssize_t vfs_copy_file_range(struct file *file_in, loff_t pos_in, * Try cloning first, this is supported by more file systems, and * more efficient if both clone and copy are supported (e.g. NFS). */ - if (file_in->f_op->clone_file_range) { + if (inode_in->i_sb == inode_out->i_sb && + file_in->f_op->clone_file_range) { ret = file_in->f_op->clone_file_range(file_in, pos_in, file_out, pos_out, len); if (ret == 0) {